DESCRIPTION

There are two well-known message buses: the systemwide message bus
(installed on many systems as the "messagebus" service) and the
per-user-login-session message bus (started each time a user logs in).
The --system and --session options direct
dbus-send to send messages to the system or session buses respectively.
If neither is specified, dbus-send sends to the session bus.

Nearly all uses of dbus-send must provide the --dest argument
which is the name of a connection on the bus to send the message to. If
--dest is omitted, no destination is set.

The object path and the name of the message to send must always be
specified. Following arguments, if any, are the message contents
(message arguments). These are given as type-specified values and
may include containers (arrays, dicts, and variants) as described below.